Breakable aerosol generating article

ABSTRACT

An aerosol generating article is provided, having a first section including a combustible heat source and an aerosol-forming substrate and a second section including a tubular element defining a recess at one end of the second section. The sections are integrally connected at a region of weakness and are separable at the region so that the element can be placed over the heat source and so that the heat source is at least partially received in the recess. The first section is upstream of the second section when the sections are integrally connected and the element is at least partially open at both ends thereof such that air may be drawn through the element. The element is either at a downstream end of the second section such that the recess forms a mouth end cavity, or is at an upstream end such that the recess forms a transfer element.

The present invention relates to an aerosol generating article, such asa smoking article, having a combustible heat source for heating anaerosol-forming substrate downstream of the combustible heat source.

A number of smoking articles in which tobacco is heated rather thancombusted have been proposed in the art. An aim of such ‘heated’ smokingarticles is to reduce known harmful smoke constituents of the typeproduced by the combustion and pyrolytic degradation of tobacco inconventional cigarettes. In one known type of heated smoking article, anaerosol is generated by the transfer of heat from a combustible heatsource to a physically separate aerosol-forming substrate, such astobacco. The aerosol-forming substrate may be located within, around ordownstream of the combustible heat source. For example,WO-A2-2009/022232 discloses a smoking article comprising a combustibleheat source, an aerosol-forming substrate downstream of the combustibleheat source, and a heat-conducting element around and in contact with arear portion of the combustible heat source and an adjacent frontportion of the aerosol-forming substrate. During smoking, volatilecompounds are released from the aerosol-forming substrate by heattransfer from the combustible heat source and entrained in air drawnthrough the smoking article. As the released compounds cool, theycondense to form an aerosol that is inhaled by the user.

Smoking articles which include a combustible fuel element or heat sourcemay have a combustion zone or zone of heating that is larger, moredense, and not as readily extinguished by crushing or “stubbing out” theheat source compared to a conventional cigarette, in which tobacco isburnt or combusted to heat and release volatile compounds from thetobacco. Such smoking articles may have a heat source that containssignificantly more energy in the form of heat than found in thecombustion zone of a conventional cigarette. Consequently, such smokingarticles may require more effort to extinguish or to remove sufficientheat to facilitate disposal.

It would be desirable to provide an improved aerosol generating article,particularly one that includes a combustible fuel element or heatsource. In particular, it would be desirable to provide an aerosolgenerating article having an element for facilitating disposal of theaerosol generating article after use and which is both simple tomanufacture and use.

According to the present invention, there is provided an aerosolgenerating article comprising: a first section having a combustible heatsource and an aerosol-forming substrate; and a second section having atubular element defining a recess at one end of the second section,wherein the first and second sections are integrally connected at aregion of weakness, the first section and second section being separableat the region of weakness to enable the tubular element to be placedover the combustible heat source, after use of the aerosol generatingarticle, such that the combustible heat source is at least partiallyreceived in the recess wherein the first section is upstream of thesecond section when the first and second sections are integrallyconnected at the region of weakness, wherein the tubular element is atleast partially open at both of its ends such that, during use of theaerosol generating article, air may be drawn along the aerosolgenerating article through the tubular element, and wherein the tubularelement is either at the downstream end of the second section, such thatthe recess forms a mouth end cavity of the aerosol generating articlewhen the first and section sections are integrally connected, or thetubular element is at the upstream end of the second section and forms atransfer element of the aerosol generating article when the first andsection sections are integrally connected.

Advantageously, the present invention provides a simple to manufactureand simple to use aerosol generating article having an integral means offacilitating disposal. By placing the tubular element over thecombustible heat source while the heat source is combusting or hot, abarrier is formed between the combustible heat source and an outersurface of the aerosol generating article. Thus, the heat source may beshielded by the tubular element until it has cooled to a sufficientlylow temperature to be disposed of easily. In some preferred embodiments,when the heat source is received in the recess, the tubular elementhinders a supply of air to the combustible heat source, facilitating theextinguishing of the combustible heat source. This may be particularlyadvantageous, since the combustion zone or zone of heating of aerosolgenerating articles having a combustible heat source is larger, moredense, and not as readily extinguished by crushing or “stubbing out”compared to a conventional cigarette.

Further, by integrally connecting the first and second sections andproviding such a tubular element as part of the second section, thetubular element is formed as an integral part of the aerosol generatingarticle. This results in a reduced chance of accidental separation ofthe tubular element from the rest of the aerosol generating article, forexample during transport or storage, in comparison to aerosol generatingarticles having a separately formed extinguisher cap. It may alsoprevent the tubular element from being mislayed, or misplaced prior touse, as may be the case with aerosol generating articles having aseparately formed extinguisher cap.

Connecting the first and second sections at a region of weaknessadvantageously allows the aerosol generating article to be split in twoby a user without undue burden by separating the first and secondsections. The tubular element can then be placed over the heat sourceafter use of the aerosol generating article. In addition, providing thetubular element as an integral part of the aerosol generating articlemitigates difficulties arising from size variations due to manufacturingtolerances that may occur when assembling aerosol generating articleshaving a separately formed extinguisher cap or heat shielding element.

The region of weakness may be present as a result of the first andsecond sections having an interface at the region. In some examples,preferably the tensile strength of any wrapping for example paper layerat the interface at the region of weekness is less than the tensilestrength of inner elements of the first section and the second sectionsuch that separation occurs in the region of the interface. Preferablythe tensile strength of the wrapping is less than 50%, or less than 20%or less than 10% of the inner elements. In some examples, the region ofweakness, for example one or more perforations or other formation isprovided at the region of weakness, for example to reduce the tensilestrength of the wrapping or other connection at the region of weakness.For example, where a metallised wrapping is present at the interface ofthe first and second sections, preferably the metallised wrappingincludes one or more perforations.

As used herein, the terms “integral” and “integrally” are used to meanthat the first and second sections share at least one component by whichthey are joined. That is, the first and second sections are joined by acomponent forming part of both the first section and the second section.For example, the first section and second section may be integrallyconnected by a wrapper forming part of both the first and secondsections. The term “integrally connected” excludes discrete first andsecond sections which are held together by friction or by fasteningmeans, such as glue or a threaded connection.

The first section, which includes the heat source and the aerosolforming substrate, is upstream of the second section when the first andsecond sections are integrally connected at the region of weakness. Thetubular element is at least partially open at both of its ends such thatduring use of the aerosol generating article air may be drawn along theaerosol generating article through the tubular element. In other words,the tubular element defines part of the airflow pathway through theassembled aerosol-generating article. With this arrangement, the firstand second sections do not require separation prior to use and mayremain integrally connected during use. Thus, the user is not requiredto hold the two separate sections during use of the aerosol generatingarticle but can separate the sections and immediately place the tubularelement over the heat source in one action. By having a tubular elementwhich defines part of the airflow pathway through the assembledaerosol-generating article, the overall length of the aerosol generatingarticle may be easily adjusted to a desired value, for example to alength similar to that of a conventional cigarette, through anappropriate choice of the length of the tubular element. Where the firstand second sections are circumscribed by a wrapper, for example an outerwrapper of the aerosol-generating article, the arrangement of thepresent invention allows the tubular element to be provided entirelywithin the outer diameter of the wrapper. This means that the outerdiameter of the assembled aerosol-generating article may besubstantially unaffected by the presence of the tubular element. Thismay be beneficial for ease of use and for overall appearance of theassembled aerosol-generating article.

In certain preferred embodiments, the tubular element is a hollow tubethat is open at both ends. In such embodiments, air may be drawn alongthe aerosol generating article through the tubular element without thetubular element having any significant effect on the resistance to drawof the aerosol generating article.

The resistance-to-draw (RTD) of an aerosol generating article refers tothe static pressure difference between the two ends of the specimen whenit is traversed by an air flow under steady conditions in which thevolumetric flow is 17.5 millilitres per second at the output end. TheRTD of a specimen can be measured using the method set out in ISOStandard 6565:2002.

Where the first section is upstream of the second section, the secondsection may form a downstream end, or mouth end, of the aerosolgenerating article. In such embodiments, the tubular element may be atany suitable position along the second section, provided that thecombustible heat source can be received in the recess defined by thetubular element when the first and second sections have been separatedat the region of weakness.

In certain embodiuments, the tubular element is at the downstream end ofthe second section and forms a mouth end cavity of the aerosolgenerating article when the first and second sections are integrallyconnected.

The tubular element may be at the upstream end of the second section andform a transfer element of the aerosol generating article. The tubularelement may be at the upstream end of the second section and form atransfer element of the aerosol generating article between theaerosol-forming substrate and a mouthpiece of the aerosol generatingarticle. The tubular element may be at the upstream end of the secondsection and form a transfer element of the aerosol generating articlebetween the aerosol-forming substrate and a mouthpiece of the secondsection.

The aerosol generating article may further comprise a removable cap atthe distal end of the first section for protecting the heat source priorto use of the aerosol generating article.

As used herein, the term ‘cap’ refers to a protective cover thatsubstantially surrounds the distal end of the aerosol generatingarticle, including the end face. By providing a removable cap, either asa separate component or with the tubular element, the user is inhibitedfrom readily igniting the heat source until the cap is removed, unlikepaper wrappers, which do not prevent or obstruct the user from ignitingthe heat source while the paper wrapper remains intact and covering theheat source. Similarly, providing a removable cap that is removed priorto ignition of the heat source may lead to a reduction in ash generationand flaming compared to aerosol generating articles with a paper wrapperthat covers the heat source during ignition. If present, a paper wrappercan burn rapidly leading to flaming and generation of ash when theaerosol generating article is ignited. The removable cap may enable amore hygienic aerosol generating article to be provided. In addition,the cap reduces the risk of the user coming into direct contact with theheat source, and so reduces the risk that the heat source will soil theuser's clothes or hands.

Similarly, during manufacture, the provision of the removable capadvantageously reduces the risk of the heat source dirtying themanufacturing equipment, and staining adjacent aerosol generatingarticles. In effect, the removable cap acts to isolate the heat sourcefrom the surrounding equipment and aerosol generating articles. Inaddition, it provides physical protection during manufacture to helpprevent the heat source from breaking or chipping off.

For example, aerosol generating articles according to the invention maycomprise a removable cap attached at a line of weakness to the distalend of the aerosol generating article, wherein the cap comprises acylindrical plug of material circumscribed by a wrapper as described inWO-A1-2014/086998.

The aerosol-forming substrate may be downstream of the heat source. Theaerosol-forming substrate may be positioned concentrically within oraround the heat source.

As used herein, the terms ‘upstream’ and ‘front’, and ‘downstream’ and‘rear’, are used to describe the relative positions of segments orcomponents of the aerosol generating article in relation to thedirection in which a user draws on the aerosol generating article duringuse thereof. Aerosol generating articles according to the inventioncomprise a mouth end and an opposed distal end. In use, a user draws onthe mouth end of the aerosol generating article. The mouth end isdownstream of the distal end. The heat source is located at or proximateto the distal end.

In any of the above embodiments the tubular element may be substantiallyrigid. With such an arrangement, the shape of the recess may besubstantially maintained during placement of the tubular element overthe combustible heat source. This facilitates receipt of the combustibleheat source in the recess after use of the aerosol generating article.

Preferably, the tubular element has a wall thickness between about 100micrometer and 300 micrometer, for example 200 micrometer. The abovementioned wall thicknesses can provide suitable stability in someexamples, for example where the tubular element comprises paper orcardboard for when the heat source is inserted into the tubular element.The tubular element may include a reinforcing formation, for example atubular insert.

When the tubular element is placed over the combustible heat sourceafter use of the aerosol generating article, the combustible heat sourceis at least partially received in the recess to facilitate disposal ofthe aerosol generating article. For example, the tubular element may bearranged such that when the combustible heat source is received in therecess, the tubular element extends along at least 90 percent of thelength of the combustible heat source, for example leaving about 1 mm ofthe length of the combustible heat source uncovered. Preferably, thetubular element is arranged such that, when the combustible heat sourceis received in the recess, the tubular element extends alongsubstantially the entire length of the combustible heat source.

Preferably, the tubular element is arranged such that, when thecombustible heat source is ignited and received within the recess, thetubular element sufficiently restricts the supply of air to thecombustible heat source that the combustible heat source is extinguishedby the tubular element. Preferably, the tubular element is substantiallyimpermeable to air. In this configuration, the gap between the externalsurface of the heat source and the internal surface of the tubularelement is preferably less than about 2 mm, more preferably less thanabout 1 mm. With this small gap, there is restricted access of oxygen tothe heat source as compared to when the heat source is free to burnwithout the tubular element. In addition, the emission of combustiongases from the heat source further restricts the flow of oxygen to theheat source because the small gap between the tubular element and theheat source reduces the mixing rate of the combustion gases with thesurrounding air.

Preferably, the tubular element is configured such that, when thecombustible heat source is received within the recess, there is africtional fit between the inner surface of the tubular element and theouter surface of the combustible heat source. Providing such africtional fit allows the tubular element to be held over thecombusibtle heat source without any additional connecting means to beprovided.

An inner surface of the tubular element may comprise a non-combustiblematerial. The tubular element may be formed from a non-combustiblematerial. An inner surface of the tubular element may be lined with anon-combustible material. Where an inner surface of the tubular elementis lined with a non-combustible material, the non-combustible materialmay be applied as a coating formed by applying one or more intumescentvarnishes, paints, lacquers, or any combination thereof on the innersurface of the tubular element. For example, by brushing, rolling,dipping or spraying or by using a non-combustible sheet that is formedinto the final shape of the tubular element by any known manufacturingprocesses, such as cutting, rolling and gluing systems. Thenon-combustible material may be at least one of: a metal; a metal oxide;a ceramic; and a stone. Further, the non-combustible material may begraphite.

As used herein, the term ‘non-combustible’ is used to describe amaterial that is substantially non-combustible at temperatures reachedby the combustible heat source during combustion and ignition thereof.

The tubular element may comprise a thermochromatic material or pigment.Thermochromatic pigments or materials change colour with respect totemperature. This has the advantage of providing a user with a visualcue of the temperature near the heat source on the aerosol generatingarticle. Furthermore, the use of a thermochromatic pigment or materialmay provide a simple visual indication of when the aerosol generatingarticle has reached a temperature that is low enough to be disposed ofwithout additional precautionary measures.

The tubular element may comprise a heat reactive material that isarranged to deform in response to heat from the combustible heat sourcewhen the combustible heat source is received in the recess such that thetubular element fits tightly against the combustible heat source toreduce the air supply to the combustible heat source.

Such an arrangement may enable the tubular element to form a seal, orpartial seal, around the combustible heat source. This may reduce, evenfurther, the time taken for the heat source to become extinguished. Inaddition, the heat reactive material may act as an improved thermalbarrier between the heat source and an external surface of the aerosolgenerating article to reduce the temperature of the external surfacerelative to embodiments in which no heat reactive material is present.

The heat reactive material may comprise an intumescent material.

As used herein, the term ‘intumescent material’ is used to describe amaterial that expands upon exposure to elevated temperatures, other thanonly as a result of its coefficient of thermal expansion.

The intumescent material may comprise any suitable material ormaterials. In certain embodiments, the intumescent material forms aninsulating foam when exposed to heat from the combustible heat source ofthe aerosol generating article. In one embodiment, the intumescentmaterial comprises a carbon source, such as starch or one or morepentaerythritols (or other types of polyalcohol), an acid source, suchas ammonium polyphosphate, a blowing agent such as melamine, and abinder, such as soy lecithin. In an alternative embodiment, theintumescent material comprises a mixture of sodium silicate and graphitesuch that a hard char foam may be produced when the intumescent materialis exposed to heat from the combustible heat source of the aerosolgenerating article.

The intumescent material may be applied as a heat reactive coatingformed by applying one or more intumescent varnishes, paints, lacquers,or any combination thereof on an interior surface of the tubularelement. For example, by brushing, rolling, dipping or spraying or byusing intumescent paper or plastic-based sheet that is formed into thefinal shape of the tubular element by any known manufacturing processes,such as cutting, rolling and gluing systems. In one embodiment, theintumescent material is a latex solution applied by spraying.

The intumescent material may expand by any suitable amount when exposedto heat from the combustible heat source of the aerosol generatingarticle. Preferably, the intumescent material expands by a factor ofbetween about 10 and about 100 times its original dimensions whenexposed to heat. Where the intumescent material is applied as a heatreactive coating on an interior surface of the tubular element,preferably the thickness of the coating is from about 10 microns toabout 100 microns and increases to from about 1 mm to about 2 mm whenexposed to heat from the combustible heat source of the aerosolgenerating article.

The heat reactive material may comprise a heat-shrink material.

As used herein, the term ‘heat shrink material’ is used to describe amaterial that shrinks as a result of heat exposure.

Where the heat reactive material comprises a heat-shrink material, theheat-shrink material may be configured to deform the tubular element tohinder air flow to the combustible heat source.

In certain embodiments, the heat shrink material may be a mechanicallyexpanded polymer layer which returns to its unexpanded dimensions as aresult of heat exposure. For example, the heat shrink material may bemanufactured from a thermoplastic material such as nylon, polyolefin,fluroropolymer (such as FEP, PTFE or Kynar), PVC, neoprene, siliconeelastomer, Viton, or any combination thereof. In certain embodiments,the heat shrink material is a fluoroplastic Kynar with a shrinktemperature of about 135° C. and a shrink ratio of about 2:1. In suchembodiments, the fluoroplastic Kynar may be provided as a layer of thematerial used to form the tubular element.

In certain embodiments, the heat shrink material is applied as a heatreactive coating on an inner surface of the tubular element. In suchembodiments, the coating may be applied by any suitable method. Forexample, the coating may be applied as a sheet or film which is adheredto the tubular element, for example by gluing or welding.

The heat reactive material may be provided along the entire length ofthe tubular element. The heat reactive material may be provided alongonly part of the length of the tubular element. The heat reactivematerial may be provided at the downstream end of the tubular element.With this arrangement, the downstream end of the tubular element mayform a seal or partial seal around the combustible heat source. This mayresult in a layer of air being present between the tubular element andthe combustible heat source, upstream of the heat reactive material toform a thermally insulating barrier.

During use of the aerosol generating article, the combustible heatsource may reach high temperatures. For example, a heat source of anaerosol generating article may reach an average temperature of around500 degrees Celsius and in certain cases the temperature of the heatsource may reach up to about 800 degrees Celsius. Thus, the tubularelement may comprise thermally insulating material arranged to reducethe temperature of an external surface of the aerosol generating articlewhen the combustible heat source is received in the recess whilecombusting or while hot. The tubular element may comprise a barriermaterial to thermally isolate the combustible heat source when thecombustible heat source is received in the recess while combusting orwhile hot. Suitable thermally insulating materials have a low thermalconductivity or substantially no thermal conductivity. Suitablethermally insulating materials may include, for example, cardboards,foams, polymers or ceramic materials, or other materials that have a lowthermal conductivity.

As used herein, the term “thermally insulating material” is used todescribe material having a bulk thermal conductivity of less than about50 milliwatts per metre Kelvin (mW/(m K)) at 23° C. and a relativehumidity of 50% as measured using the modified transient plane source(MTPS) method.

The tubular element may be formed from a suitable barrier material suchas a substantially non-combustible material or a substantially flameretardant material. Preferably, the barrier material is thermally stablein air at the highest temperature achieved by the heat source of theaerosol generating article. Suitable barrier materials may, for example,include metallic materials, or ceramic materials.

The tubular element may comprise one or more materials that undergo aphase change when heated. The tubular element may comprise one or morematerials that melt and extinguish the heat source by flowing over theheat source and eliminating or restricting oxygen supply to the heatsource. The tubular element may comprise one or more materials thatundergo an endothermic reaction or phase change and consume heat energyproduced by the heat source, thereby cooling the heat source. Thetubular element may comprise one or more materials that decompose whenbrought in contact with the heat source and produce a decompositionproduct that extinguishes the heat source. Examples of materials thatmay undergo a phase change when in proximity to the heat source include,for example, certain polymers and waxes.

The tubular element may comprise one or more materials selected from thegroup consisting of barrier materials, non-combustible materials, flameretardant materials, thermally conductive materials, thermallyinsulating materials, foam materials, phase-changing materials, metallicmaterials, and ceramic materials. For example, the tubular element maycomprise one or more materials selected from the group consisting ofnon-combustible materials, flame-retardant materials, thermallyconductive materials and thermally insulating materials.

In some embodiments, the tubular element may comprise a heat-reflectivematerial which advantageously may modulate the heat radiating from thecombustible heat source.

As used herein the term ‘heat reflective material’ refers to a materialthat has a relatively high heat reflectivity and a relatively low heatemissivity such that the material reflects a greater proportion ofincident radiation from its surface than it emits. Preferably, thematerial reflects more than 50% of incident radiation, more preferablymore than 70% of incident radiation and most preferably more than 75% ofincident radiation.

The tubular element may be formed from a composite material, such as amaterial comprising a plurality of layers. The layers of the compositematerial for the tubular element may be formed from two or more of thematerials described herein. For example, the tubular element may beformed from material comprising an external insulating layer, a secondlayer of intumescent or heat reactive material, and an internal layer ofnon-combustible material.

The tubular element may reduce the emission of undesirable odours whenthe combustible heat source is received in the recess. The tubularelement may reduce the emission of odours by comprising a material whichabsorbs or adsorbs the odours.

Alternatively, or in addition, the tubular element may comprise aheat-released flavour compound. The flavour compound may be ananoparticle formed from a low melting point wax encapsulating theflavour compound. The flavour compound is preferably volatile such thatit is released into the atmosphere on activation of the nanoparticle.

The tubular element may be tapered. The tubular element may besubstantially cylindrical in shape. The tubular element may have anysuitable cross-sectional shape, for example, circular, oval, orpolygonal.

The region of weakness is a region at which the aerosol generatingarticle is easily broken in order to separate the first and secondsections. The region of weakness may be formed by a region of weaknessin one or more internal components of the aerosol generating article.For example, the region of weakness may be formed by a local reductionin thickness of one or more internal components of the aerosolgenerating article. The region of weakness may be formed by a joinbetween two or more internal components of the aerosol generatingarticle.

The region of weakness may be an area of weakness. In preferredembodiments, the region of weakness is a line of weakness along whichthe first and second sections are separable.

The aerosol generating article preferably comprises a wrapper thatcircumscribes at least a portion of the first section and at least aportion of the second section. The wrapper enables the first and secondsections to be integrally connected during manufacture. The region ofweakness may comprise a weakness formation provided in the wrapper.

The weakness formation may comprise a local reduction in thickness ofthe wrapper. For example, the weakness formation may comprise one ormore ablated regions or lines, one or more scored lines, or acombination thereof. The weakness formation may comprise a section ofdifferent, weaker, wrapper material. The weakness formation may comprisea plurality of perforations in the wrapper. The plurality ofperforations may extend around at least a portion of the aerosolgenerating article. The plurality of perforations may circumscribe theaerosol generating article.

The wrapper may be affixed to the first section and to the secondsection, remote from the region of weakness. By affixing the wrapperremote from the region of weakness, the wrapper may be more easilybroken at the region of weakness when the user wants to separate thefirst and second sections. The wrapper is preferably affixed to thefirst and second sections using glue. The glue may be provided in a lineextending from, or adjacent to, the distal end of the aerosol generatingarticle towards the mouth end of the aerosol generating article. Theline of glue may be interrupted adjacent to, or at, the line ofweakness.

The wrapper may be a cigarette paper. A cigarette paper may be anysuitable material for wrapping components of an aerosol generatingarticle in the form of a rod. The cigarette paper may circumscribe thecomponent elements of the aerosol generating article such that the papergrips the component elements of the aerosol generating article when thearticle is assembled and hold them in position within the rod. Suitablematerials are well known in the art.

The region of weakness, and thus the location at which the aerosolgenerating article is separable into discrete first and second sections,may be provided at any suitable distance along the aerosol generatingarticle. Preferably, the region of weakness is located at least 10 mmfrom either end of the aerosol generating article. More preferably, theregion of weakness is located at least 20 mm from either end of theaerosol generating article. This arrangement allows the user to separatethe first and second sections and place the tubular element over theheat source without having to hold either the first or second sectionsat a position particularly close to the combustible heat source,reducing the risk of the user being exposed to high surface temperaturesnear the heat source, or to soiling from the combustible heat source.

In certain particular embodiments, the region of weakness is locatedfrom about 10% to about 90% along the length of the aerosol generatingarticle, where 0% refers to the upstream end and 100% refers to theupstream end, or mouth end, of the aerosol generating article. Theregion of weakness may be located from about 20% to about 80% along thelength of the aerosol generating article, from about about 30% to about70% along the length of the aerosol generating article, or from about40% to about 60% along the length of the aerosol generating article. Inone particular embodiment, the the region of weakness is located atabout 50% along the length of the aerosol generating article.

Aerosol-generating articles according to the present invention comprisea first section having a combustible heat source and an aerosol formingsubstrate. The aerosol-generating articles may comprise a plurality ofelements assembled in the form of a rod.

As used herein, the term ‘aerosol-generating article’ is used to denotean article comprising an aerosol-forming substrate that is capable ofreleasing volatile compounds that can form an aerosol. Anaerosol-generating article may be a non-combustible aerosol-generatingarticle, which is an article that releases volatile compounds withoutthe combustion of the aerosol-forming substrate. An aerosol-generatingarticle may be a heated aerosol-generating article, which is anaerosol-generating article comprising an aerosol-forming substrate thatis intended to be heated rather than combusted in order to releasevolatile compounds that can form an aerosol. A heated aerosol-generatingarticle may comprise an onboard heating means forming part of theaerosol-generating article, or may be configured to interact with anexternal heater forming part of a separate aerosol-generating device

An aerosol-generating article may be a smoking article that generates anaerosol that is directly inhalable into a user's lungs through theuser's mouth. An aerosol-generating article may resemble a conventionalsmoking article, such as a cigarette. An aerosol-generating article maycomprise tobacco. An aerosol-generating article may be disposable. Anaerosol-generating article may be partially-reusable and comprise areplenishable or replaceable aerosol-forming substrate.

The combustible heat source is preferably a solid heat source, and maycomprise any suitable combustible fuel including, but not limited to,carbon and carbon-based materials containing aluminium, magnesium, oneor more carbides, one or more nitrides and combinations thereof. Solidcombustible heat sources for heated smoking articles and methods forproducing such heat sources are known in the art and described in, forexample, U.S. Pat. No. 5,040,552 and U.S. Pat. No. 5,595,577. Typically,known solid combustible heat sources for heated smoking articles arecarbon-based, that is they comprise carbon as a primary combustiblematerial.

The combustible heat source may be a combustible carbonaceous heatsource.

The combustible heat source is preferably a blind combustible heatsource.

As used herein, the term ‘blind’ describes a heat source that does notcomprise any air flow channels extending from the front end face to therear end face of the combustible heat source. As used herein, the term‘blind’ is also used to describe a combustible heat source including oneor more airflow channels extending from the front end face of thecombustible heat source to the rear end face of the combustible heatsource, wherein a combustible substantially air impermeable barrierbetween the rear end face of the combustible heat source and theaerosol-forming substrate barrier prevents air from being drawn alongthe length of the combustible heat source through the one or moreairflow channels.

The inclusion of one or more closed air passageways increases thesurface area of the blind combustible heat source that is exposed tooxygen from the air and may advantageously facilitate ignition andsustained combustion of the blind combustible heat source.

Aerosol generating articles according to the invention comprising blindcombustible heat sources comprise one or more air inlets downstream ofthe rear end face of the combustible heat source for drawing air intoone or more airflow pathways through the aerosol generating article.Aerosol generating articles according to the invention comprisingnon-blind combustible heat sources may also comprise one or more airinlets downstream of the rear end face of the combustible heat sourcefor drawing air into one or more airflow pathways through the aerosolgenerating article.

In some embodiments, aerosol generating articles according to theinvention comprising blind combustible heat sources comprise one or moreair inlets located proximate to the downstream end of theaerosol-forming substrate.

In use, air drawn along the one or more airflow pathways of aerosolgenerating articles according to the invention comprising a blindcombustible heat source does not pass through any airflow channels alongthe blind combustible heat source. The lack of any airflow channelsthrough the blind combustible heat source advantageously substantiallyprevents or inhibits activation of combustion of the blind combustibleheat source during puffing by a user. This substantially prevents orinhibits spikes in the temperature of the aerosol-forming substrateduring puffing by a user. By preventing or inhibiting activation ofcombustion of the blind combustible heat source, and so preventing orinhibiting excess temperature increases in the aerosol-formingsubstrate, combustion or pyrolysis of the aerosol-forming substrateunder intense puffing regimes may be advantageously avoided. Inaddition, the impact of a user's puffing regime on the composition ofthe mainstream aerosol may be advantageously minimised or reduced.

The inclusion of a blind combustible heat source may also advantageouslysubstantially prevent or inhibit combustion and decomposition productsand other materials formed during ignition and combustion of the blindcombustible heat source from entering air drawn through aerosolgenerating articles according to the invention during use thereof. Thisis particularly advantageous where the blind combustible heat sourcecomprises one or more additives to aid ignition or combustion of theblind combustible heat source.

In aerosol generating articles according to the invention comprising ablind combustible heat source, heat transfer from the blind combustibleheat source to the aerosol-forming substrate occurs primarily byconduction. Heating of the aerosol-forming substrate by forcedconvection is minimised or reduced. This may advantageously help tominimise or reduce the impact of a user's puffing regime on thecomposition of the mainstream aerosol of articles according to theinvention.

In aerosol generating articles according to the invention comprising ablind combustible heat source, it is particularly important to optimisethe conductive heat transfer between the combustible heat source and theaerosol-forming substrate. As described further below, the inclusion ofone or more heat-conducting elements around at least a rear portion ofthe combustible carbonaceous heat source and at least a front portion ofthe aerosol-forming substrate is particularly preferred in aerosolgenerating articles according to the invention including blind heatsources, where there is little if any heating of the aerosol-formingsubstrate by forced convection.

In certain embodiments of the invention, the combustible heat sourcecomprises at least one longitudinal airflow channel, which provides oneor more airflow pathways through the heat source. The term “airflowchannel” is used herein to describe a channel extending along the lengthof the heat source through which air may be drawn through the aerosolgenerating article. Such heat sources including one or more longitudinalairflow channels are referred to herein as “non-blind” heat sources.

The diameter of the at least one longitudinal airflow channel may bebetween about 1.5 mm and about 3 mm, more preferably between about 2 mmand about 2.5 mm. The inner surface of the at least one longitudinalairflow channel may be partially or entirely coated, as described inmore detail in WO-A-2009/022232.

In embodiments of aerosol generating articles that are conventionallit-end cigarettes, the heat source will be a volume of tobacco.

As used herein, the term “aerosol-forming substrate” is used to describea substrate capable of releasing upon heating volatile compounds, whichcan form an aerosol. The aerosols generated from aerosol-formingsubstrates of aerosol generating articles according to the invention maybe visible or invisible and may include vapours (for example, fineparticles of substances, which are in a gaseous state, that areordinarily liquid or solid at room temperature) as well as gases andliquid droplets of condensed vapours.

The aerosol-forming substrate may be a solid aerosol-forming substrate.Alternatively, the aerosol-forming substrate may comprise both solid andliquid components. The aerosol-forming substrate may comprise atobacco-containing material containing volatile tobacco flavourcompounds, which are released from the substrate upon heating.Alternatively, the aerosol-forming substrate may comprise a non-tobaccomaterial. The aerosol-forming substrate may further comprise one or moreaerosol formers. Examples of suitable aerosol formers include, but arenot limited to, glycerine and propylene glycol.

The aerosol-forming substrate may be a rod comprising atobacco-containing material.

If the aerosol-forming substrate is a solid aerosol-forming substrate,the solid aerosol-forming substrate may comprise, for example, one ormore of: powder, granules, pellets, shreds, spaghetti strands, strips orsheets containing one or more of: herb leaf, tobacco leaf, fragments oftobacco ribs, reconstituted tobacco, homogenised tobacco, extrudedtobacco and expanded tobacco. The solid aerosol-forming substrate may bein loose form, or may be provided in a suitable container or cartridge.For example, the aerosol-forming material of the solid aerosol-formingsubstrate may be contained within a paper or other wrapper and have theform of a plug. Where an aerosol-forming substrate is in the form of aplug, the entire plug including any wrapper is considered to be theaerosol-forming substrate.

Optionally, the solid aerosol-forming substrate may contain additionaltobacco or non-tobacco volatile flavour compounds, to be released uponheating of the solid aerosol-forming substrate. The solidaerosol-forming substrate may also contain capsules that, for example,include the additional tobacco or non-tobacco volatile flavour compoundsand such capsules may melt during heating of the solid aerosol-formingsubstrate.

Optionally, the solid aerosol-forming substrate may be provided on orembedded in a thermally stable carrier. The carrier may take the form ofpowder, granules, pellets, shreds, spaghetti strands, strips or sheets.The solid aerosol-forming substrate may be deposited on the surface ofthe carrier in the form of, for example, a sheet, foam, gel or slurry.The solid aerosol-forming substrate may be deposited on the entiresurface of the carrier, or alternatively, may be deposited in a patternin order to provide a non-uniform flavour delivery during use.

The aerosol-forming substrate may be in the form of a plug or segmentcomprising a material capable of emitting volatile compounds in responseto heating circumscribed by a paper or other wrapper. Where anaerosol-forming substrate is in the form of such a plug or segment, theentire plug or segment including any wrapper is considered to be theaerosol-forming substrate.

The aerosol-forming substrate preferably has a length of between about 5mm and about 20 mm. In certain embodiments, the aerosol-formingsubstrate may have a length of between about 6 mm and about 15 mm or alength of between about 7 mm and about 12 mm.

The aerosol-forming substrate may comprise a plug of tobacco-basedmaterial wrapped in a plug wrap. In preferred embodiments, theaerosol-forming substrate comprises a plug of homogenised tobacco-basedmaterial wrapped in a plug wrap.

In any of the above embodiments, the combustible heat source and theaerosol-forming substrate may be in abutting coaxial alignment. As usedherein, the terms “abutting” and “abut” are used to describe acomponent, or a portion of a component, being in direct contact withanother component, or portion of a component.

Aerosol generating articles according to the invention may comprise aheat-conducting element around and in direct contact with both at leasta rear portion of the combustible heat source and at least a frontportion of the aerosol-forming substrate. In such embodiments, theheat-conducting element provides a thermal link between the combustibleheat source and the aerosol-forming substrate of aerosol generatingarticles according to the invention and advantageously helps tofacilitate adequate heat transfer from the combustible heat source tothe aerosol-forming substrate to provide an acceptable aerosol.

Alternatively or in addition, aerosol generating articles according tothe invention may comprise a heat-conducting element spaced apart fromone or both of the combustible heat source and the aerosol-formingsubstrate, such that there is no direct contact between theheat-conducting element and one or both of the combustible heat sourceand the aerosol-forming substrate.

Where the aerosol generating article comprises a heat-conducting elementaround at least a rear portion of the combustible heat source and atleast a front portion of the aerosol-forming substrate, theheat-conducting element may be formed by the wrapper. For example, thewrapper may comprise one or more layers of heat conductive materialwhich form the one or more heat-conducting elements.

The one or more heat-conducting elements are preferably non-combustible.In certain embodiments, the one or more heat-conducting elements may beoxygen restricting. In other words, the one or more heat-conductingelements may inhibit or resist the passage of oxygen through theheat-conducting element.

Suitable heat-conducting elements include, but are not limited to: metalfoil wrappers such as, for example, aluminium foil wrappers, steelwrappers, iron foil wrappers and copper foil wrappers; and metal alloyfoil wrappers.

Aerosol generating articles according to the invention may comprise atransfer element, or spacer element, downstream of the aerosol-formingsubstrate. Such an element may take the form of a hollow tube that islocated downstream of an aerosol-forming substrate.

The transfer element may abut one or both of the aerosol-formingsubstrate and a mouthpiece. Alternatively, the transfer element may bespaced apart from one or both of the aerosol-forming substrate and themouthpiece.

The inclusion of a transfer element advantageously allows cooling of theaerosol generated by heat transfer from the combustible heat source tothe aerosol forming substrate. The inclusion of a transfer element alsoadvantageously allows the overall length of the aerosol generatingarticle to be adjusted to a desired value, for example to a lengthsimilar to that of a conventional cigarette, through an appropriatechoice of the length of the transfer element.

The transfer element may have a length of between about 7 mm and about50 mm, for example a length of between about 10 mm and about 45 mm or ofbetween about 15 mm and about 30 mm. The transfer element may have otherlengths depending upon the desired overall length of the aerosolgenerating article, and the presence and length of other componentswithin the aerosol generating article.

The term “transfer element” refers to an element which comprises atleast one open-ended tubular hollow body. When the aerosol-generatingarticle is in its assembled state, that is, when first and secondsections are integrally connected at the region of weakness, thetransfer element provides a hollow body defining part of the airflowpathway through the article. Where the aerosol-generating articlecomprises a transfer element, in use, air drawn into the aerosolgenerating article passes through the at least one open-ended tubularhollow body of the transfer element as it passes downstream through theaerosol generating article from the aerosol-forming substrate to thedistal end of the aerosol generating article.

The transfer element may comprise at least one open-ended tubular hollowbody formed from one or more suitable materials that are substantiallythermally stable at the temperature of the aerosol generated by thetransfer of heat from the combustible carbonaceous heat source to theaerosol-forming substrate. Suitable materials are known in the art andinclude, but are not limited to, paper, cardboard, plastics, such acellulose acetate, ceramics and combinations thereof.

In embodiments of aerosol generating article in which the first section,which includes the heat source and the aerosol forming substrate, isupstream of the second section when the first and second sections areintegrally connected at the region of weakness and the tubular elementis a hollow tube that is open at both ends, the transfer element maycomprise the tubular element. The transfer element may be formed by thetubular element.

Aerosol generating articles according to the invention may comprise anaerosol-cooling element or heat exchanger downstream of theaerosol-forming substrate. The aerosol-cooling element may comprise aplurality of longitudinally extending channels.

The aerosol-cooling element may comprise a gathered sheet of materialselected from the group consisting of metallic foil, polymeric material,and substantially non-porous paper or cardboard. In certain embodiments,the aerosol-cooling element may comprise a gathered sheet of materialselected from the group consisting of polyethylene (PE), polypropylene(PP), polyvinylchloride (PVC), polyethylene terephthalate (PET),polylactic acid (PLA), cellulose acetate (CA), and aluminium foil.

In certain preferred embodiments, the aerosol-cooling element maycomprise a gathered sheet of biodegradable polymeric material, such aspolylactic acid (PLA) or a grade of Mater-Bi® (a commercially availablefamily of starch based copolyesters).

Preferably, the aerosol generating article comprises a mouthpiecedownstream of the aerosol-forming substrate and positioned at thedownstream end of the aerosol generating article. The mouthpiece mayform part of the first section or the second section. The mouthpiece maybe provided as a separate component, or as part of a third section thatis integrally connected to the first or second sections, either directlyor via one or more intermediate components.

The mouthpiece may comprise a filter. For example, the mouthpiece maycomprise a filter plug having one or more segments. Where the mouthpiececomprises a filter plug, preferably the filter plug is a single segmentfilter plug. The filter plug may comprise one or more segmentscomprising cellulose acetate, paper or other suitable known filtrationmaterials, or combinations thereof. Preferably, the filter plugcomprises filtration material of low filtration efficiency.

The aerosol generating article may be substantially cylindrical inshape. The aerosol generating article may be substantially elongate. Theaerosol generating article has a length and a circumferencesubstantially perpendicular to the length.

The aerosol-forming substrate may be substantially cylindrical in shape.The aerosol-forming substrate may be substantially elongate. Theaerosol-forming substrate also has a length and a circumferencesubstantially perpendicular to the length. The aerosol-forming substratemay be located in the aerosol generating article such that the length ofthe aerosol-forming substrate is substantially parallel to the airflowdirection in the aerosol generating article.

The transfer section or element may be substantially elongate.

The aerosol generating article may have any desired length. For example,the aerosol generating article may have a total length of betweenapproximately 65 mm and approximately 100 mm.

The aerosol generating article may have any desired external diameter.For example, the aerosol generating article may have an externaldiameter of between approximately 5 mm and approximately 12 mm.

The aerosol generating article may be circumscribed by an outer wrapperof, for example, cigarette paper, which has low air permeability.Alternatively or in addition, the mouthpiece may be circumscribed bytipping paper.

It should also be appreciated that particular combinations of thevarious features described and defined in any aspects of the inventioncan be implemented and/or supplied and/or used independently.

The invention will be further described, by way of example only, withreference to the accompanying drawings in which:

FIG. 1 shows a schematic longitudinal cross-sectional view of a firstembodiment of a smoking article according to the present invention;

FIG. 2 shows a schematic longitudinal cross-sectional view of thesmoking article of FIG. 1, in which the smoking article is in anextinguishing configuration;

FIG. 3 shows a schematic longitudinal cross-sectional view of a secondembodiment of a smoking article according to the present invention;

FIG. 4 shows a schematic longitudinal cross-sectional view of thesmoking article of FIG. 3, in which the smoking article is in anextinguishing configuration;

FIG. 5 shows a schematic longitudinal cross-sectional view of a thirdembodiment of a smoking article, which is included for backgroundinterest only; and

FIG. 6 shows a schematic longitudinal cross-sectional view of thesmoking article of FIG. 5, in which the removable cap is removed.

The smoking article 100 according to the first embodiment of theinvention shown in FIG. 1 comprises a blind combustible carbonaceousheat source 102, an aerosol-forming substrate 104, an airflow directingelement 106, an aerosol-cooling element 108, and a mouthpiece 110 inabutting coaxial alignment. The combustible carbonaceous heat source102, aerosol-forming substrate 104 and airflow directing element 106 areoverwrapped in a first outer wrapper 112 of cigarette paper of low airpermeability, forming a first section 114 of the smoking article 100.The aerosol-cooling element 108 and mouthpiece 110 are overwrapped in asecond outer wrapper 116 of cigarette paper of low air permeability,forming a second section 118 of the smoking article 100. The firstsection 114 is thus upstream of the second section 118. The smokingarticle 100 further includes a band of tipping paper 120 circumscribingat least a downstream portion of the first section 114 and at least anupstream portion of the second section 118. The first section 114 andthe second section 118 are integrally connected by the tipping paper 120along a first line of weakness 122 which comprises a plurality ofperforations that circumscribe the smoking article 100. The first lineof weakness 122 defines a weakness formation in the tipping paper 120.

A removable cap 124 is provided at the distal end of the smoking article100, and is directly adjacent to the heat source 102. The removable cap124 comprises a central portion 126, and is wrapped in a portion 128 ofthe first outer wrapper 112. In the embodiment shown, the centralportion 126 comprises a desiccant, such as glycerine, provided topreferentially absorb moisture as compared to the heat source. Theportion 128 of the first outer wrapper is connected to the rest of thefirst outer wrapper 112 along a second line of weakness 130. The line ofweakness 130 comprises a plurality of perforations in the first outerwrapper 112 that circumscribe the smoking article 100.

The aerosol-forming substrate 104 is located immediately downstream ofthe combustible carbonaceous heat source 102 and comprises a cylindricalplug 132 of tobacco material, comprising glycerine as an aerosol former,that is circumscribed by plug wrap 134.

A non-combustible, substantially air impermeable barrier 136 is providedbetween the downstream end of the combustible heat source 102 and theupstream end of the aerosol-forming substrate 104. As shown in FIG. 1,the non-combustible, substantially air impermeable barrier consists of anon-combustible, substantially air impermeable, barrier coating 136,which is provided on the entire rear face of the combustiblecarbonaceous heat source 102.

A heat conducting element (not shown) consisting of a tubular layer ofaluminium foil surrounds and is in direct contact with a rear portion ofthe combustible carbonaceous heat source 102 and an abutting frontportion of the aerosol-forming substrate 104.

The airflow directing element 106 is located downstream of theaerosol-forming substrate 104 and comprises an open-ended, substantiallyair impermeable hollow tube 138 made of, for example, cardboard, whichis of reduced diameter compared to the aerosol-forming substrate 104.The upstream end of the open-ended hollow tube 138 abuts theaerosol-forming substrate 104. The open-ended hollow tube 138 iscircumscribed by an annular air permeable diffuser 140 made of, forexample, cellulose acetate tow, which is of substantially the samediameter as the aerosol-forming substrate 104.

The open-ended hollow tube 138, and annular air permeable diffuser 140may be separate components that are adhered or otherwise connectedtogether to form the airflow directing element 106 prior to assembly ofthe smoking article 100. In yet further embodiments, the open-endedhollow tube 138 and annular air permeable diffuser 140 may be parts of asingle component. For example, the open-ended hollow tube and annularair permeable diffuser may be parts of a single hollow tube of airpermeable material having a substantially air impermeable coatingapplied to its inner surface.

In a particularly preferred embodiment the central portion 116 of theremovable cap 114 is manufactured from the same material as the airflowdirecting element, and so comprises an open-ended substantially airimpermeable hollow tube circumscribed by an annular air permeablediffuser.

As shown in FIG. 1, a circumferential arrangement of air inlets 142 isprovided in the first outer wrapper 112 circumscribing the first section114 in the region of the airflow directing element 106.

The aerosol-cooling element 108 is located immediately downstream of theairflow directing element 106 and comprises a gathered sheet ofbiodegradable polymeric material, such as, for example, polylactic acid.

The mouthpiece 110 of the smoking article 100 is located immediatelydownstream of the aerosol-cooling element 108 and comprises a filtersegment 144, having a cylindrical plug 146 of suitable filtrationmaterial such as, for example, cellulose acetate tow of very lowfiltration efficiency circumscribed by filter plug wrap 148, and atubular element 150 immediately downstream of the filter segment 144.The tubular element 150 comprises a cylindrical tube of suitable,substantially rigid material such as, for example cardboard, stiff paperor heat resistant rigid plastic. The tubular element 150 defines arecess 152 at the mouth end of the smoking article 100. The mouthpiece110 thus has a mouth end cavity formed by the recess 152.

To use the smoking article 100, the user removes the removable cap 124by transversely compressing the cap by pinching it between thumb andfinger. By compressing the cap 124, sufficient force is provided to thesecond line of weakness 130 to locally break the first outer wrapper112. The user then removes the cap 124 by twisting the cap to break theremaining portion of the second line of weakness 130. When the cap 124is removed the heat source 102 is partially exposed which enables theuser to light the smoking article 100.

In use, the user ignites the combustible heat source 102 which heats theaerosol-forming substrate 104 to produce an aerosol. When the userinhales on the mouthpiece 110 air is drawn through the air inlets 142,through the aerosol-forming substrate 104, airflow directing element106, aerosol-cooling element 108, and mouthpiece 110, as indicated bythe arrows in FIG. 1, and into the user's mouth.

After use of the smoking article 100, the user breaks the smokingarticle in two by breaking the tipping paper 120 along the first line ofweakness 122 to separate the first section 114 and the second section118 across separation plane 1000. The user then places the downstreamend of the second section 118 over the upstream end of the first section114 so that the combustible heat source 102 is received in the recess152 of the tubular element 150, as shown in FIG. 2.

In the extinguishing configuration shown in FIG. 2, the tubular element150 is a frictional fit over the combustible heat source 102, such thatit is retained over the combustible heat source 102 and the first andsecond sections 114, 188 are held together. The tubular element 150,which may be made from any suitable material, such as flame-retardantmaterial, sufficiently restricts the supply of oxygen to the combustibleheat source so that the heat source extinguishes, and thus cools down.In this way, the user is provided with a simple and self-contained meansof extinguishing the combustible heat source after use of the smokingarticle.

Further, the tubular element may be provided with a fragrance that maybe evolved when the tubular element is heated by the combustible heatsource. The fragrance may be released into the atmosphere and may act tomask any unpleasant odours released by the heat source as it is beingextinguished. The fragrance may provide an air freshening effect byemitting pleasant odours and fragrances. Preferably the fragrance issufficiently volatile that it swiftly evaporates after the tubularelement is placed over the combustible heat source.

In preferred embodiments the fragrance may include one or more fragranceingredient selected from the list consisting of Amyl Cinnamal,Amylcinnamyl Alcohol, Benzyl Alcohol, Benzyl Salicylate, CinnamylAlcohol, Cinnamal, Citral, Coumarin, Eugenol, Geraniol,Hydroxycitronellal, Hyroxymethylpentylcyclohexenecarboxaldehyde,lsoeugenol, Anisyl Alcohol, Benzyl Benzoate, Benyl Cinnamate,Citronellol, Farnesol, Hexyl Cinnamaldehyde2-methyl-3-(4-tert-butylbenzyl)propionaldehyde, d-Limonene, Linalool,Methyl heptine carbonate, and 3-Methyl-4-(2,6,6-trimethyl-2-cyclohexen-1-yl)-buten-2-one.

FIGS. 3 and 4 show a second embodiment of a smoking article 300. Thesmoking article 300 is of similar construction to the first embodimentof smoking article 100 shown in FIGS. 1 and 2, and where the samefeatures are present, like reference numerals have been used. However,as shown in FIG. 3, the tubular element 350 of smoking article 300 ofthe second embodiment is located immediately upstream of theaerosol-cooling element 308 and is at the upstream end of the secondsection 318, rather than at the downstream end of the second section.The recess 352 defined by the tubular element 350 forms a transferelement, or spacer element, between the airflow directing element 306and the aerosol-cooling element 308. Instead of having a mouth endcavity formed by the tubular element, as in the first embodiment ofsmoking article shown in FIG. 1, the mouthpiece 310 and mouth end of thesmoking article 300 are formed by the filter segment 344.

To use the smoking article 300, the user removes the removable cap 324,in the same way as described with reference to FIGS. 1 and 2, topartially expose the combustible heat source 302 which enables the userto light the smoking article 300.

In use, the user ignites the combustible heat source 302 which heats theaerosol-forming substrate 304 to produce an aerosol. When the userinhales on the mouthpiece 310 air is drawn through the air inlets 342,through the aerosol-forming substrate 304, airflow directing element306, tubular element 346, aerosol-cooling element 308, and mouthpiece310, as indicated by the arrows in FIG. 3, and into the user's mouth.

After use of the smoking article 300, the user breaks the smokingarticle in two by breaking the tipping paper 320 along the first line ofweakness 322 to separate the first section 314 and the second section318 across separation plane 3000. The user then places the upstream endof the second section 318 over the upstream end of the first section 314so that the combustible heat source 302 is received in the recess 352 ofthe tubular element 350, as shown in FIG. 4.

In the extinguishing configuration shown in FIG. 4, as with the smokingarticle 100 of the first embodiment, the tubular element 350 is africtional fit over the combustible heat source 302, such that it isretained over the combustible heat source 302 to sufficiently restrictthe supply of oxygen to the combustible heat source so that the heatsource extinguishes, and thus cools down. In this embodiment, the recess352 defined by the tubular element 350 preferably has a length greaterthan that of the exposed portion of the heat source 302 received in therecess 352. This avoids direct contact between the combustible heatsource 302 and the aerosol-cooling element 308, reducing the risk ofexposing the aerosol-cooling element 308 to excessive heat from the heatsource during extinguishing which may otherwise result in the emissionof unpleasant odours from melting of the aerosol-cooling element 308.

Alternatively, or in addition, the tubular element 350 may comprise athermally insulating material to reduce the heat transfer from the heatsource 302 to the aerosol-cooling element 308 during extinguishing.

FIGS. 5 and 6 show a third embodiment of smoking article 500 which isincluded for background interest only. The smoking article 500 issimilar to the first and second embodiments of smoking article 100, 300shown in FIGS. 1 to 4, and where the same features are present, likereference numerals have been used. However, with the smoking article 500of the third embodiment, the first section 514 is downstream of thesecond section 518 and comprises comprises a blind combustiblecarbonaceous heat source 502, an aerosol-forming substrate 504, anairflow directing element 506, an aerosol-cooling element 508, atransfer element 509 and a mouthpiece 510 in abutting coaxial alignment.As with the smoking article 300 of the second embodiment, the mouthpiece510 and mouth end of the smoking article 500 are formed by filtersegment 544.

The combustible carbonaceous heat source 502, aerosol-forming substrate504 and airflow directing element 506 are overwrapped in a first outerwrapper 512 of cigarette paper of low air permeability, forming a firstpart of the first section 514. The aerosol-cooling element 508, transferelement 509 and mouthpiece 510 are overwrapped in a second outer wrapper516 of cigarette paper of low air permeability, forming a second part ofthe first section 514. The first section 514 further includes a band oftipping paper 520 circumscribing at least a downstream portion of thefirst outer wrapper 512 and at least an upstream portion of the secondouter wrapper 516 to hold the two parts of the first section 514together.

As with the smoking articles 100, 300 of the first and secondembodiments, smoking article 500 also includes a removable cap 524 atthe distal end of the smoking article 500 and directly adjacent to theheat source 502. The removable cap 124 comprises a central portion 526,and is wrapped in a portion 528 of the first outer wrapper 512. Theportion 528 of the first outer wrapper which circumscribes the cap 524is connected to the rest of the first outer wrapper 512 along a line ofweakness 522. The line of weakness 522 comprises a plurality ofperforations in the first outer wrapper 512 that circumscribe thesmoking article 500. The line of weakness 522 defines a weaknessformation in the first outer wrapper 512.

Unlike the smoking articles 100, 300 of the first and secondembodiments, in this embodiment, the tubular element 550 is provided aspart of the cap 524, forming the second section 514 of the smokingarticle 500. The tubular element 550 circumscribes the central portion526 of the cap 524 and at least part of the length of the heat source502. In this manner, the heat source 502 is received in the recess 552defined by the tubular element 550 prior to use of the smoking article.The portion 528 of the first outer wrapper 512 which circumscribes thecap also circumscribes the tubular element 550 and integrally connectsthe first section 514 and the second section 518.

To use the smoking article 500, the user separates the first and secondsections 514, 518 across separation plane 5000 by twisting the cap 524and the tubular element 550 to break the first outer wrapper 512 alongthe line of weakness 522 and separate the first portion 528 of wrapperfrom the rest of the first outer wrapper 512. When the first and secondsections 514 518 are separated, as shown in FIG. 6, the heat source 502is partially exposed enabling the user to light the smoking article 500.

In use, the user ignites the combustible heat source 502 which heats theaerosol-forming substrate 504 to produce an aerosol. When the userinhales on the mouthpiece 510 air is drawn through the air inlets 542,through the aerosol-forming substrate 504, airflow directing element506, aerosol-cooling element 508, transfer element 509 and mouthpiece510, as indicated by the arrows in FIG. 6, and into the user's mouth.

After use of the smoking article 500, the user returns the secondsection 518 to its initial position at the upstream end of the firstsection 514 so that the combustible heat source 502 is received in therecess 552 of the tubular element 550. In this position, the tubularelement 550 is a frictional fit over the combustible heat source 502 andsufficiently restricts the supply of oxygen to the combustible heatsource so that the heat source extinguishes, and thus cools down.

In all of the above described embodiments, the tubular element maycomprise an intumescent material, or heat-shrink material which reactsto the heat of the combustible heat source to further restrict thesupply of oxygen to the heat source when the smoking article is in theextinguishing configuration. The intumescent or heat-shrink material mayalso at least partially close the open end of the tubular element tofurther restrict the supply of oxygen to the heat source. In addition toyet further restricting the supply of oxygen, the at least partiallyclosed end of the tubular element may provide a physical barrier betweenthe heat source and any external materials.

The specific embodiments and examples described above illustrate but donot limit the invention. It is to be understood that other embodimentsof the invention may be made and the specific embodiments and examplesdescribed herein are not exhaustive.

1.-12. (canceled)
 13. An aerosol generating article, comprising: a firstsection having a combustible heat source and an aerosol-formingsubstrate; and a second section having a tubular element defining arecess at one end of the second section, wherein the first section andsecond section are integrally connected at a region of weakness, thefirst section and second section being separable at the region ofweakness to enable the tubular element to be placed over the combustibleheat source, such that the combustible heat source is at least partiallyreceived in the recess, wherein the first section is upstream of thesecond section when the first section and second section are integrallyconnected at the region of weakness, wherein the tubular element is atleast partially open at both ends thereof, such that air may be drawnalong the aerosol generating article through the tubular element, andwherein the tubular element is either at a downstream end of the secondsection, such that the recess forms a mouth end cavity of the aerosolgenerating article when the first section and second section areintegrally connected, or the tubular element is at an upstream end ofthe second section and forms a transfer element of the aerosolgenerating article when the first section and second section areintegrally connected.
 14. The aerosol generating article according toclaim 13, wherein the tubular element is arranged such that, when thecombustible heat source is received in the recess, the tubular elementextends along substantially an entire length of the combustible heatsource.
 15. The aerosol generating article according to claim 13,wherein the tubular element is arranged such that, when the combustibleheat source is ignited and received within the recess, the tubularelement sufficiently restricts a supply of air to the combustible heatsource so that the combustible heat source is extinguished by thetubular element.
 16. The aerosol generating article according to claim15, wherein the tubular element is dimensioned such that, when thecombustible heat source is received within the recess, there is africtional fit between an inner surface of the tubular element and anouter surface of the combustible heat source.
 17. The aerosol generatingarticle according to claim 13, wherein an inner surface of the tubularelement comprises a non-combustible material.
 18. The aerosol generatingarticle according to claim 17, wherein the non-combustible material isat least one of a metal, a metal oxide, a ceramic, and a stone.
 19. Theaerosol generating article according to claim 13, wherein the tubularelement comprises a heat reactive material that is configured to deformin response to heat from the combustible heat source when thecombustible heat source is received in the recess such that the tubularelement fits tightly against the combustible heat source to restrict anair supply to the combustible heat source.
 20. The aerosol generatingarticle according to claim 19, wherein the heat reactive materialcomprises an intumescent material.
 21. The aerosol generating articleaccording to claim 19, wherein the heat reactive material comprises aheat-shrink material.
 22. The aerosol generating article according toclaim 13, wherein the region of weakness is a line of weakness.
 23. Theaerosol generating article according to claim 13, wherein the firstsection and the second section are circumscribed by a wrapper, andwherein the region of weakness comprises a weakness formation providedin the wrapper.
 24. The aerosol generating article according to claim23, wherein the weakness formation comprises a plurality of perforationsin the wrapper, the plurality of perforations circumscribing the aerosolgenerating article.
 25. The aerosol generating article according toclaim 13, wherein the region of weakness is located at least about 10 mmfrom either end of the aerosol generating article.
 26. The aerosolgenerating article according to claim 13, wherein the region of weaknessis located at least about 20 mm from either end of the aerosolgenerating article.